A voltage detector is a device that determines the presence/absence of an electrical charge in an object. In some examples, a voltage detector is implemented as a simple piece of testing hardware that indicates the presence of electricity. In other examples, a voltage detector is implemented as an advanced tool that detects precise voltage levels in electrical systems.
Electronic devices frequently employ a voltage detector to indicate if a particular voltage is outside a specified range. For example, a battery operated device often includes a voltage detector to provide a low voltage indication when the voltage supplied by a battery decreases below a predetermined level. In some examples, the low voltage indication notifies a user of the device that the battery should be replaced or recharged.